Fabrication and biocompatibility of poly(L-lactic acid) and chitosan composite scaffolds with hierarchical microstructures

The scaffold microstructure is crucial to reconstruct tissue normal functions. In this article, poly(L-lactic acid) and chitosan fiber (PLLA/CTSF) composite scaffolds with hierarchical microstructures both in fiber and pore sizes were successfully fabricated by combining thermal induced phase separation and salt leaching techniques. The composite scaffolds consisted of a nanofibrous PLLA matrix with diameter of 50-500 nm, and chitosan fibers with diameter of about 20 pm were homogenously distributed in the PLLA matrix as a microsized reinforcer. The composite scaffolds also had high porosity (>94%) and hierarchical pore size, which were consisted of both micropores (50 nm-10 mu m) and macropores (50-300 mu m). By tailoring the microstructure and chemical composition, the mechanical property, pH buffer and protein adsorption capacity of the composite scaffold were improved significantly compared with those of PLLA scaffold. Cell culture results also revealed that the PLLA/CTSF composite scaffolds supported MG-63 osteoblast proliferation and penetration. (C) 2016 Elsevier B.V. All rights reserved.